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37 Cards in this Set
- Front
- Back
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base metals in general value?
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comparitively low because of poor corrosion resistance.
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what are the scarce base metals?
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copper
lead zinc tin mercury cadmium |
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Cu - what is it used for ?
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50% building and construction
20% electrical |
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Cu Resources -- how is it formed?
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through hydrothermal vein and disseminated deposits. Hot water circulatiing through rocks above shallow magmas--beneath volcanoes.
Hydrothermal fluids dissolve and concentrate metals in solution Metals precipitate (form solid crystals) as: Veins - Bonanza type deposits in the overlying volcanic rock spiderweb of small veins. |
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copper is one mineral?
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no, several: Chalcopyrite CuFeS2 ("peacock ore")
Chalcocite Cu2S |
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Porphyry Cu Deposits
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occur in the
upper portion of the magma chamber as thin veins (<1 mm) Low-grade , more than 50% of world Cu production is porphyry deposits. |
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whati s Porphyry
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two different igneous textures
- change in magma cooling rate |
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Cu Porphyries are hydrothermal deposits that form
along which type of tectonic plate boundaries? |
Convergent.
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Volcanogenic Massive Sulfide (VMS) deposits
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Hydrothermal fluids concentrate metals from oceanic crust then VENT onto the
sea floor at divergent plate boundaries (mid ocean ridges) Rapid cooling causes precipitation of Fe, Cu, Pb, and Zn sulfides |
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VMS deposits -- at which type of plate tectonics?
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divergent
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Cu production..which countries and global prod?
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>50 countries produce Cu ore
Chile U.S. Peru ~50% of global production US imports 35% |
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US Cu reserves?
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US has 7% of global reserves - mostly in AZ
17 mines produce 99% of U.S. Cu |
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Recycled Cu -- how much of US consumption?
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10% of US consumption
from recycled Cu |
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Cu mining--how?
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Ground ore is concentrated
using froth flotation. Concentrate (25-30% Cu) is roasted Burn off sulfur as SO2 Produces impure Cu matte. Matte is refined electrolytically Cu bars, sheets, and rods. Electrolytic Copper, sulfric acid heap leaching. |
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Ground copper ore tcan be concentrated using____?
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froth flotation.
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SCARCE BASE METALS: which two base metals are found together?
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Lead and Zinc
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TF VMS deposits usually form near convergent boundaries?
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F, divergent.
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the mineralogical gap is the time between usage of ___ and ___
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high grade ore and low grade ore.
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88% of the lead used by us is for?
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transportation
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the bright color in minerals Azurite Malachite and Chalcopyrite come from this elemet, which is something eologists look for when exploring for tihs ore
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copper.
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the high ___ cost of aluminum limits smelting to industrialized countries
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electricity
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aluminum is abudnance int he silicate mineral group, but is only economically mind from Bauxide which is part of the____ group?
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Hydroxide
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Zn - why is it essential for life?
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an essential bio nutrient toxic in high concentrations
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Pb - what's lead for?
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soft, malleable with low melting point lead water pipes, glass, eating utensiles.
--mostly for Transportation 88% Vehicle batteries, fuel tanks, bearings, ammunition glass xray. lead is toxic to humans. |
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Zinc what's Zn for?
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Galvanizing -- process of coat iron or steel with a thin layer of another metal -- commonly Zinc because ti protects from corrosion.
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what does Cu Zn alloy make?
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Brass
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what does Cu Sn tin alloy make?
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Bronze
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Three important geologic deposit types
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1.) VMS
2. Sediment-hosted deposits 3.) mississippi valley type deposits. |
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VMS -- deposits
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same as Cu -- hot water Hydrothermal fluid circulating through rocks above shalllow magma beneath volcanoes.
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Sediment-hosted deposits
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Zn and Pb in groundwater’s migrating
through sandstones deposit sulfide ore minerals Red Dog mine is shallow and flat-lying = open-pit minin |
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"Mississippi Valley Type" deposits
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Form in limestones by hot brines (hydrothermal fluids) migrating out of
deep sediment-filled basins Numerous Pb-Zn MVT districts in east- |
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where is 1/3 of pb and zn reserves?
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Australia.
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Recycling supplies ~ pb
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75% of US consumption vehicle battery trade-ins
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Zn where is most of it from?
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75% of it from Alaska's Red Dog Mine
U.S. is the world's biggest Zn concentrate exporter and Zn metal importer |
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How are Most mississippi valley deposits mined?
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using the room and pillar method.
Ores are concentrated by froth flotation then smelted with coke to form metals |
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what are transport costs
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High transport costs Pb (heavy)
10% of metal's cost |
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prophry Cu depostis form in relatively small sized area of hydrothermal activity located near volcanic acitvity TF
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false, large.
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